Craig Heffner, the same researcher who uncovered a backdoor in routers from D-link, found the latest problem. He uncovered the functionality, which ships with Tenda's products, after unpacking firmware updates and locating what he described as "suspicious code".

Attackers could take over the router and execute commands by sending a UDP packet with a special string, The Hacker News claims.

"The backdoor only listens on the LAN, thus it is not exploitable from the WAN. However, it is exploitable over the wireless network, which has WPS enabled by default with no brute force rate limiting,” Heffner explains in a detailed advisory.

“My shiny new ReaverPro box made relatively short work of cracking WPS,” he claimed, “providing access to the WLAN and a subsequent root shell on the router.”

Heffner claims the backdoor exists on Tenda’s W302R and W330R router models as as well as re-branded models, such as the Medialink MWN-WAPR150N.